A preferred embodiment of the present invention generally relates to transesophageal probes, and more particularly relates to an improved transesophageal ultrasound probe having a rotating endoscope shaft.
Various medical conditions affect internal organs and structures. Efficient diagnosis and treatment of these conditions typically require a physician to directly observe a patient""s internal organs and structures. For example, diagnosis of various heart ailments often requires a cardiologist to directly observe affected areas of a patient""s heart. Instead of more intrusive surgical techniques, ultrasound imaging is often utilized to directly observe images of a patient""s internal organs and structures.
Transesophageal Echocardiography (TEE) is one approach to observing a patient""s heart through the use of an ultrasound transducer. TEE typically includes a probe, a processing unit, and a monitor. The probe is connected to the processing unit which in turn is connected to the monitor. In operation, the processing unit sends a triggering signal to the probe. The probe then emits ultrasonic signals into the patient""s heart. The probe then detects echoes of the previously emitted ultrasonic signals. Then, the probe sends the detected signals to the processing unit which converts the signals into images. The images are then displayed on the monitor. The probe typically includes a semi-flexible endoscope that includes a transducer located near the end of the endoscope.
Typically, during TEE, the endoscope is introduced into the mouth of a patient and positioned in the patient""s esophagus. The endoscope is then positioned so that the transducer is in a position to facilitate heart imaging. That is, the endoscope is positioned so that the heart or other internal structure to be imaged is in the direction of view of the transducer. Typically, the transducer sends ultrasonic signals through the esophageal wall that come into contact with the heart or other internal structures. The transducer then receives the ultrasonic signals as they bounce back from various points within the internal structures of the patient. The transducer then sends the received signals back through the endoscope typically via wiring. After the signals travel through the endoscope, the signals enter the processing unit typically via wires connecting the endoscope to the processing unit.
Often, in addition to the heart, it may be desirable to image other internal structures within the body of a patient. Imaging other internal structures may require re-positioning of the probe in order to view the internal organs. Additionally, viewing the heart and/or other internal structures from various angles and perspectives may require re-positioning of the probe.
FIG. 1 illustrates a conventional transesophageal ultrasound probe 100 according to one embodiment of the prior art. The probe 100 includes a control handle 110, a fixed endoscope shaft 120 fastened to the distal end of the control handle 110, and a system cable 130 attached to the proximal end of the control handle 110. The fixed endoscope shaft 120 includes a scanhead 122 located at the distal end of the fixed endoscope shaft 120. The scanhead 122 includes an imaging element 124, such as a transducer (not shown). The control handle 110 includes imaging controls 112 mounted on the control handle 110. The imaging controls 112 include imaging control wheels 114 and scan plane push buttons 116 that control the orientation of the seanhead 122. The imaging element 124 is connected to a processing unit (not shown) via wiring (not shown) that extends through the scanhead 122 and throughout the length of the body of the probe 100. The wiring in the probe 100 is then connected via the system cable 130 to the processing unit. The processing unit is then connected via wiring to a monitor (not shown) for display of the image.
In operation, the fixed endoscope shaft 120 of the probe 100 is introduced into the esophagus of a patient. The fixed endoscope shaft 120 is then positioned via the control handle 110 so that the internal structure to be imaged is within the field of view of the imaging element 124 located on, or within, the scanhead 122. Typically, the probe 100 is axially rotated to position the desired internal structure in the field of view of the imaging element 124. In order to rotate the endoscope shaft 120, the entire probe 100 must be rotated. That is, the control handle 110 must be rotated so that the imaging element 124 may image internal structures from different angles and perspectives. For example, to rotate the direction of view 124 of the imaging element of the scanhead 122 by 30xc2x0, the control handle 110 typically needs to be rotated 30xc2x0 because the fixed endoscope shaft 120 is firmly fixed to the control handle 110. Thus, the fixed endoscope shaft 120 is not allowed to rotate independently of the control handle 110. Therefore, as the control handle 110 is rotated by 30xc2x0, the imaging controls 122 will also be rotated by 30xc2x0. Unfortunately, rotating the imaging controls 122 often may cause confusing and/or counter-intuitive operation of the probe 100. That is, because the imaging controls 112 are fixed, it may be difficult or impossible for an operator to obtain the images he/she desires. Further, observing the resulting images from the physically rotated probe may be confusing. The confusion may lead to misdiagnosis, risks of injury and/or increased time to perform the imaging procedure.
Therefore, a need has existed for a transesophageal ultrasound probe that provides greater and easier access to images of a patient""s internal structures. Further, a need has also existed for a transesophageal ultrasound probe that facilitates more intuitive imaging of internal structures from various angles and perspectives.
The present invention relates to an internal imaging probe for use in a medical imaging system. The probe includes a rotating shaft, such as a rotating endoscope shaft, having an imaging element, such as a transducer, mounted on the distal end of the rotating shaft. The probe also includes a control handle for controlling the imaging element. Preferably, a rotating tube within the probe extends through the rotating shaft into the control handle. The rotation of the rotating tube causes the rotating shaft to rotate. The rotating shaft rotates relative to, and independently of, the control handle to which it is connected. Washers and O-rings provide low friction connections between the rotating tube located in the probe and the control handle.
Preferably, the rotating shaft is rotated via a rotation control wheel located at the distal end of the control handle. The rotation control wheel is fastened or bonded to the rotating tube so that manual rotation of the control wheel causes the rotating tube, and therefore the rotating shaft, to rotate. Because the rotating shaft rotates, an imaging element located on, or within, the rotating shaft also rotates. The rotating shaft may also be set in a locked position so that the rotating shaft may be configured, or preset, to various rotated positions.
Alternatively, the rotation of the rotating shaft may be fully automated. The automated probe may include a motor fixed to a fixed portion of the shaft, or to the control handle. The motor also includes a driving cog wheel, or gear system, that operatively engages a driven cog wheel, or gear system, attached to a rotating portion of the shaft. The rotation of the rotating shaft may then be controlled by levers, potentiometers, or other such devices located on the control handle.